Call-distributing switch.



MEETS-41mm 1.

E'RISTENSBN.

0000000000000 OQ@ 000000000000000 o V.: G l CALLMSTEIBUTIN@ SWITCH.AZPLIOATIGNNFILED JUH; 23, 1906.

MEETS-SHEET 2.

.gammadi .May 3l, 3.91).

P. V. CHBS'I".EI\TSEN;V CALI DISTRIBUTING? SWITCH. PPLIOATIOH HLED. JUNE2s, 190e.

PETER VALDEMAR CHRSTENSEN, OF COPENH-.GEL ENMARK, ASIG'NOR TO AKTIE-BOLAGET L. M. ERICSSON t CO., GF STOCKHOLM, SEDEN.

UNITED smrns Para CALL-DISTRIBUTING SWITCH.

Specification of Letters atent.

Patent-militair 3i, i910.

Application filed .Tune 23, 1906. ySerial No. 323,l00. l

To all whom it 'may concern.'

t by the present invention,

Be it known that I, PEiER-,VALDnMAR' In the heretofore usual telephonearrangements the subscribers lines are, at the change, divided intogroups, each one consisting of a number of lines, corresponding to theaverage etiioieney of a. single operator. It appears hoWevei',-even it,with due regard to the empirical number of calls from the subscribersconcerned, by means of the .so-called intermediate distributingtields,the lilies of the various groups are so distributed, that each operatormight be expected to get,

a uniform share of the work,-that, in the .:ourse of time, matters Willbe altered, so

that the individual operators will, again be unevenly oeeupied, andbesides it may happen, that one ot the positions is crowded with work,during certain hours ot the day, while other positions are(.-oniparatively short ot' work. This state ol thiiigscauses delays anduncertainty in the telephone service, as wel] as overirfu'liiugr ot' theoperators at they unduly busy positions.V These bad conditionsl may ol:lr-ourse be remedied by planning;r the exehangie so that the number olElilies belonging( to earh group is made small enough to enable theopeiators, at any time, even at the busiest positions, to perform theexchange service with ease, but this arrangement necessarilv means aheavy first oost and a numerous operatingr stati". An attenil'it hasbeen made to remedy the beforementioned draw-bach. by terniiiuitingilthe subscribers lines at a peculiarly constructed distriluition board:t'roin where they are, 'when a call is made. su'itelud onto anyinult'ijile board operator happening\,tov be idle at the given moment;this method however causes too great a delay in the operating.,TliisldraW-back is completely removed the improvement being attained insuch a manner that when the subscribers call, automatically opera torhappening to be The ma the line to be bel engi ne; ing` lines,

matie switxhing ing; a contact belonging toone of line Wires, starting'the motion of connections are made and instantaneously with the idle atthe moment. in4 feature of the invention is that connected with an idleline certain group of distributas a main line., to an anto device, thelatter, by elosthe main a group to a is run oicontact springs, until oneof these, sliding along' a. contact row, reaches a, coiitaetcorresponding to an idle distributing line whereby a cited ai id neeessary Qn the.

sri-called search magnet is ein consequently closes the contacts, forthe desired connection.

accompanying drawings, Figure l is a longitudinal verticalsectionoiilthe switching tribution. same.

7, and 8 Figs. 3, (1mb, e-f, and f--e respectively.

device used for the automatic dis- Fig'. 2 is a bottoni-view of the 4-and 5 are moss-sections Figs. 6, are wiring diagramsshowing, by

way of example, how the circuits may be arranged.

in the subscribers lines a. are of one hundred, group shown onsubsei'iboi"s l arrangenient shown in Fig. 6 the divided into-'groupsthere being; but a single the drawing', and on each ine provided anautomatic switch 15 adapted to connect the subseriberls line with common.t

run to th any oi' the distributingv linesA c o all the automaticswitches in the These distributing` lines are e stations of a certainnumber'ot operators, for instance one to each ot tit teen, or threelines to each oi tive dili'erent stations.

dra Wing.

For' the salie ol elearness, only shown on tho At. each station (Zterminates a certain number ot' distributing lines, thirty itor instan di tte re n t Y.illu h the ce, starting,r 'from as many or fewer groupset automatic switches. numbers chosen, by Yay of ex*- aniple, oneoperator serves two hundred "subseribers.y but each o Berater niaVr l)i' means oi" the distriluiting lines e, be connected with au;r one otthree thousand .subseribers The du upon the his line with one K .linesterminating atthe stat'ioiiot' an idle operator,

ties oli the autouiatie` switch are, call o't a subscriber, to conne-etof the idle dlstribntingand there to indicate the call, be-

to he blocked, until. thefoperator, after the clearing-ott' signal,opens the connection.

Fig. 7 shows another arrangement of the circuit Where again thesubscribers lines are divided into groups of one hundred. Qn the drawingis shown but a single group. For cach of the latter is provided acertain number, fifteen for instance, of distributing lines c,terminating at a Certain number of positions (Z, for instance one forany one of fifteen. (En the drawing are shown only eight distributinglines c, each one of which terminates at an operating station ol. lneach distributing line o is inserted an automatic switch o', adapted tonialre connection between the said line and an)v one of the hundredsubscribers lines o in toe group. ln addition there is provided a mainautomatic switch. e, arranged to he actuated by a suhscriocfs call toselect an idle automatic switch which it then sets into action, in sucha manner that the latter (o) makes connec tion `oetween itscorresponding distributing line Hand the calling subscribeus line n. liesides the two wiring diagrams shown by way oit example, various otherWiring niente niay he used for the automatic tribution. rl-he action ot'the automatic switching device illustrated in Figs. l-- of thc drawingwill he understood from the following.

Referring to the drawings, l is a cylinder wherein a piston 2 may bemoved by .nieans oi compressed air admitted into the cylinder, through atube 3 and a Valve 4, the valve stein 5 passing looselji7 through thewall of the valve housing and resting against the armature 7 ,of anelectro-magnet (S. By means of a spring 8 the armature of theelectroonaguet (l is, when the line is idle, kept, in its lowerposition, so that the inlet from the compressed air pipe to the oyhinder is closed, While the latter is in open connection with theatmosphere; when now the electroinagnet tl, which in the followingdescription is Called the controlling magnet, attracts its armature 7,the 'valve Ll will open, giving access for the compressed air andsluxlting oil the open air inlet. The piston 2 will then move toward theright.

To. the piston is xed a hollow piston rod Sl, carrying at its extremeend, toward the right, an electro-magnet '10, hereinafter called thesearch-magnet. During the niotion ot' the piston, the magnet l0 isguided by the pins l2 sliding in the guides ll. when the controllingmagnet (3 drops its armature 7, and consequently the Valve'l enters itslowerposition, the piston 2 with the piston rod J and the search magnet.1G are drawn back hy means of a steel hand lil, attached to thecircumference oir' the 'hollow 10 pressed against the end -pulley le,containing a spiral spring, the

outer end of which is fastened to the pulley .4, While its inner end isfastened to the middle part of the lined axle of the puliev. A contactspring l5 is fastened to the searchvroagnen or to other parts movingwith the piston 2; this spring has electrical connection with one end ofthe coil of the magnet 10 and during the movement of the piston slidesalong contact row 1'?, containing' one Contact more than the nuniher ofdistrib ating lines c to oe connected with the automatic switch. Theother end of the coil of the Search magnet l() is connected 'with thecent-ral battery 32, through the armature and working contact of thesuosciihcrs linerelay 3l (Fig. S), Each contact i'n the contact rowconnected, hy means of clistributing line c., to an operating stat-ional,

and also thron'h tno switch 33, there provided, connected to the ground34, so that the Contact at is made, as long as cor responding positionand distributing line is free,`while it is open, as long as the stationor the line is lousy. The one end of the coil of the controlling magnet(l is eonnected with the ground 34, While its other end, as the armatureof the subscribers line-relay 3l is attracted, becomes conn-r otherterminal of the battery, s call causes forward motion toward the ight ofthe `piston 2 and the Search magnet l0, Well as ot the contact springl5.

During the movement to the right, the pins 18 (Figs. l, 2, connected byineens ot a link system to the search magnet l0, ollowthe rectilinearrails 19 in the guides ll, but when the Contact spring l5 touches acontee' l? that has connection with an idle distributing line c, andthereby with an idle o eratingg station, as well as with the groune,then the search magnet lt) will reeeive current front the battery by theWay of 3l, l0, l5, l?, c, 33, 3ft-g it will new attract its armature QQ,and consequently lift the pins i8, so that, the latter are deviated intothe corresponding branclior' sidetrack 2l, pointing upward in a slantingdirection. This movement is continued, until the pins 1 8 have reached.the bottoni or' this individual Side track; during the last part of theincrement the pine "i8 and the armature 2G are raised still more, andall the parts are held in this position, even if the Contact spring mayperhaps have lea the cont-act 17. As the controlling inagnet 6 remainsexcited, the air pressure remainsl acti e and keeps the searcli..1nagnetof the Sidetrack. @n a plate 22, astened to the armature 20 are tiltedthree contact springs ).l,the latter igeing, oy flexible wire, connectedto the line wires B5 Fig. 8) and to the suoscribers test wire 3o. vWhenthe armature of the search magnet, l0 is attracted, and the pins eil tothe' that a contact, a motor, a member moved by the motor3 a Contactcarried by the member and trawelng over 'the series of select-ingContacts, a Search magnet in circuit With the Contact carried by themember, a pluralby of contacts carried by he member and adapted toengage the series of Speaking and sgnnliug Coutucs, but norma'ilysuppoxed S0 1S to not engage the series of contacts during 'themoven'lent of said member, and n, lacking means operated by 'the Search11mg;- ne and adapted to stop the travel of H19,

moved membef against the force of the Cx'ving motor and i0 ransfer cheforce of motor so as i0 move and press he plurality of movable conctsagainst cont-acts of th sffres of speaking and signaling contacts.

ln testmny whereof have signed my name i0 hs Specification 1u thepresence of two subscribing Witnesses.

VVnesses:

' JULIUS LEHMANN,

HERMAN RE.

